SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d28db6cf8d3d38056ac35895eb1ee34de88638caf184b18094b24754e0698e9' 
  AND token = 'U8SYYdzXTJLDtRSu8g4yx5CX4lgu5C+q1CxYWh3lvyU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}